Nevertheless, the Doctor was adventuring on his own for about a third of the series. Because it posits a number of stories between Rose's departure and Martha Jones' arrival, and again between Journey's End and Planet of the Dead, it suggests that the gap between the Tenth Doctor's companions was relatively large. Overall, the Battles in Time strip suggests that the Tenth Doctor may have been without a companion as much as he was with one. Almost all pencils and inks were handled on the series by Lee Sullivan.