In June 1984, Paul Kantner, the last remaining founding member of Jefferson Airplane, left Jefferson Starship, and then took legal action over the Jefferson Starship name against his former bandmates. Kantner settled out of court and signed an agreement that neither party would use the names "Jefferson" or "Airplane" unless all members of Jefferson Airplane, Inc. (Bill Thompson, Paul Kantner, Grace Slick, Jorma Kaukonen, Jack Casady) agreed. The band briefly changed its name to Starship Jefferson while legal proceedings occurred, but ultimately the name was reduced to Starship. Freiberg stayed with the band after the lawsuit and attended the first studio sessions for the next album. He became frustrated with the sessions because all the keyboard work in the studio was being done by Peter Wolf (who had played on the sessions for Nuclear Furniture and briefly joined the band on the road for the follow-up tour) and that was the instrument Freiberg was supposed to be playing. He left the band and the next album was finished with the five remaining members. In 1984, Gabriel Katona (who had previously played in Rare Earth and Player) joined the band to play keyboards and saxophone on the road with them through the end of 1986.
The next album, Knee Deep in the Hoopla was released in October 1985 and scored two No. 1 hits. The first was "We Built This City", written by Bernie Taupin, Martin Page, Dennis Lambert, and Peter Wolf and was engineered by Grammy-winning producer Bill Bottrell and arranged by Bottrell and Jasun Martz; the second was "Sara". The album itself reached No. 7, went platinum, and spawned two more singles: "Tomorrow Doesn't Matter Tonight" (#26), and "Before I Go" (#68). The band had not had a No.1 hit record since the original Jefferson Starship released Red Octopus in 1975.
In early 1987, "Nothing's Gonna Stop Us Now" was featured in the film Mannequin and hit No. 1, although only Slick and Thomas (plus Craig Chaquico's guitar solo) appeared on it. At that time, the song made Slick the oldest female vocalist to sing on a number-one Billboard Hot 100 hit, at the age of 47, (She held this record until Cher broke it at the age of 52, in 1999 with "Believe".) The following year, the band's song "Wild Again" (which reached No.73 on the Billboard singles chart) was used in the movie Cocktail.
By the time No Protection was released, bassist and keyboardist Pete Sears had left the band. Sears went on to play keyboards with former Jefferson Airplane members Jorma Kaukonen and Jack Casady in Hot Tuna for ten years. Starship's No Protection was not released until well after "Nothing's Gonna Stop Us Now" (its most popular single) had peaked on the charts, and went gold; in addition to "Nothing's Gonna Stop Us Now" (#1), it featured the singles "It's Not Over ('Til It's Over)" (#9), and "Beat Patrol" (#46). The last song on the album, "Set The Night To Music", would later become a huge hit when re-recorded as a duet between Roberta Flack and Maxi Priest. For the No Protection tour, Brett Bloomfield was brought in to replace Sears and Mark Morgan was their new stage keyboardist.
Grace Slick left Starship in 1988, going on to join the reformed Jefferson Airplane, for one album in 1989, before announcing that she was retiring from music. As Kantner, Sears and Freiberg had left the band, all the new and remaining members were more than a decade younger than she was. To this day Slick maintains that old(er) people "don't belong on a rock and roll stage".
With Thomas the sole lead singer, the revamped lineup released Love Among the Cannibals in August 1989 and went on another tour to support the album. On September 24, 1989, while the band was in Scranton, Pennsylvania for a show, Donny Baldwin and Mickey Thomas got into a bar fight which resulted in Baldwin beating Thomas so badly that Thomas needed facial reconstructive surgery. The remainder of the tour was postponed and Baldwin was quickly fired.