Doctor Who's new sidekick FREEMA AGYEMAN is preparing to team up with the Time Lord in the British TV show for the first time later this year (06) - but she fears her predecessor Billie Piper will be a hard act to follow. The 27-year-old can't wait to play new assistant MARTHA JONES in the hit sci-fi series, and is hoping to win over Piper's fans. She says, "It still hasn't sunk in. Billie built up an amazing fan base, but I hope the fans are willing to go on new adventures with me." Piper's character ROSE will be killed off in this weekend's (08JUL06) episode.